Forming metal parts



July 4, 1939'. R. c. INGERSOLL j 2,164,523

FORMING METAL PARTS Filed Aug. 14, 1937 2 Sheets-Sheet 1 By C figge "sell ximm 2 4 1y4,1939. R. c. INGERSOLL I 2,16 ,523

FORMING METAL PARTS Filed Aug. 14, 1937 2 Sheets-Sheet 2 Patented July 4, 1939 UNITED STATES FORMING METAL PARTS Roy 0. Ingersoll, Oak Park, Ill., assignor to Borg- Warner Corporation, Chicago, 11]., a corporation of Illinois Application August 14,

3 Claims.

This invention relates to an apparatus for quenching materials.

In the manufacture of certain articles, such as tie rods, axles and the like, it is necessary to condition the material for the use to which it is to be put, by suddenly cooling or quenching the material. Unless the material is controlled during the quenching, it may. undergo a change in size or shape or both, with the result that portions which are to be held to predetermined di mensions and spacings do not measure up to the requirements set for them. In the case of tie rods, for example, it is necessary that the eyes be maintained at a predetermined spacing, but under the usual quenching procedure the rod undergoes such a change in size as to render it necessary to form the eyes separately and to weld them to the rod after the rod has been quenched to insure a proper spacing for the eyes.

The object of this invention is an improved apparatus by which materials may be quenched in their completeform without undergoing a material change in essential dimensions.

7 A feature of this invention is a dieforholding the material while it is being quenched, the area of the material in contact with the die being .a minimum to expose a large portion of the. surface of the material to the action of a refrigerant.

Another feature of this invention is a means.

for maintaining a constant spacing for critical portions of the material to be quenched.

which 0 Fig. 1 is a side elevation in section of a quenching die embodying the principles of this invention;

Fig. 2 is a plan view of the bottom die showing a portion of a tie rod in place;

Fig. 3 is a side view of the bottom die;

Fig. 4 is a bottom view of the upper die and associated water system, with a portion of the die cut away to showthe central chamber and jet forming means, and

1937, Serial No. 159,087 (Cl. 2666) Fig. 5 is a perspective of the portion of the die which holds the eye of the tie rod during the quenching.

The same reference characters are used to designate similar parts throughout the various figures of the drawings.

In its preferred form, this invention comprises a quenching die made up of a bottom die and, an upper die. The bottom die is provided with a land for supporting the material to be quenched l0 and with pins for pinning critically spaced portions of the material to the die. The upper die isprovided with a central chamber which is connected by a series of passageways to recesses located over the material .to be quenched. The recesses are separated by lands which contain a portion shaped to fit over. and contact the material when the die is closed The chamberis connected by pipes to a source of refrigerant, and afoot-operated valve controls the flow through the pipes. For purposes of illustration this invention will be described with reference toa quenching die for tie rods although it isadapted for. use in connection with quenching. other materials. i

Referring now to the drawings for a detailed description. of the invention, In is a bottom die which is provided with a raised portion or land I I for supporting a tie rod 12. Immediately over bottom die I0 is the upper die l3 which is reciprocable with respectto bottom die ID to permit the insertion and removal of tie rod l2 from the quenching die. .Any suitable means for separating the upper and lower dies may be used. The upper die I3. is provided with a chamber M- which is connected by one or more pipes l5 to a header it. A refrigerant such as water under pressure supplied from a pump 35 is fed to header l6 through a control valve I! and a flexible hose l8. Valve ll may be operated by means of a pedal I9 I connected through link 20 to valve l'l.

Tie rod I2 is provided at its extremities with eyes 2|, the spacing between which is assumed critical. Accordingly, bottom die 10 is provided with pins 22 which are adapted to be threaded through eyes 2 l and through correspondingaperture's 23 in machined inserts 24 secured to upper die l3. Pins 22 are designed to permit slight movement of the eyes in a direction. which will not materially affect the spacing therebetween. Land II is preferably shaped so that it provides a line contact with tie rod l2. This type of contact insures a minimum area of the tie rod in contact with the land and consequently a maximum area of the tie rod exposed to the action of the refrigerant.

Immediately over tie rod I2, in upper die I3, is a plurality of recesses 25, separated by relatively thin lands 26. These recesses are connected to chamber M by means of jet forming passageways 21 which are inclined so as to direct a stream upon tie rod I2 when upper die 13 is lowered. To simplify the construction, one wall of recess 25 may be made substantially normal to the axis of passageways 2'! to permit these passageways to be readily drilled from the outside. Lands 26 contain circular notches 28 which fit over tie rod l2 and clamp it to land ll of bottom die Ill. The edges 29 of notches 28 are rounded to decrease the area of tie rod l2 in contact with the notch.

It is apparent from Figure 1, that with tie rod l2 clamped between upper and lower dies l3 and [0 respectively, a space 30 is formed between the parts of the die by reason of land H. Circulation of the refrigerant through the die is therefore accomplished from header 16 through chamber l4, passageways 21, recesses 25 and space 39 to the exterior of the die. Suitable drains (not shown) may be used for disposing of the water as it leaves the die.

The quenching of a tie rod is accomplished as follows:

The tie rod is first heated to a temperature at which internal stresses in the material are removed, and with upper die l3 raised, it is placed upon land II in its heated condition with pins 22 threaded through eyes 21 Tierod I2 is previously formed by drop-forging or otherwise, and is substantially shaped as shown in Figure 2. With the hot rod in place, upper die I 3 is lowered until the rod is clamped securely between notches 28 and land ll. Pin 22 is likewise threaded through aperture 23 and insert 24, and the rod is therefore held against vertical motion. Pins 22 are supported at both ends, i. e., they are held at one end by lower die l0 and at the other end by upper die l3, and are therefore fully capable of resisting any material changes in the spacing between eyes 2!.

With tie rod l2 securely clamped between the upper and lower dies, foot pedal I9 is depressed, thereby opening valve l1 and admitting a re frigerant, such as water under pressure through flexible hose l8 and header l6 into chamber l4 wherein a uniform pressure is built up almost instantaneously. The water is then forcibly projected through passageways 2'! upon the hot tie rod l2, almost completely inundating the entire rod at once. The water then leaves the die through the space 30 between upper die l3 and lower die In. The flow is allowed to continue for a few seconds and is then stopped by releasing foot pedal [9. Upper die 13 may then be raised and rod l2 removed from lower die In.

Since the tie rod was heated to the temperature at which internal stresses are relieved, the quenching operation cools the rod through the hardening and critical temperatures so that when the rod is removed from the quenching die, it is set and does not thereafter change its shape. While it was being cooled, however, it was constrained against motion in any direction by the pins in the dies and by the clamping action of the lands between the jets on the upper die and the land on the lower die. It emerges from the die completely hardened and with no change in shape, and therefore requires no subsequent hand straightening operation before it is ready for use. Since hand straightening operations are expensive, a great reduction is effected in the cost of making the tie rods.

The quenching action is extremely rapid due to the high velocity of the water, the simultaneous action of the jets and the large area of the rod exposed to the jets. Since chamber I4 is common to all of the passageways, the pressure at each passageway is the same, and the quenching action is therefore uniform along the entire length of the rod. The fiat land I I used with the round rod insures a line contact between the rod and land and a maximum area of the rod exposed to the water.

It is understood that objects other than tie rods may be quenched in accordance with this invention and that the dies used therewith may be changed in accordance with the shape of such other objects. Similarly, other refrigerants beside water may be used. It is understood further that the foregoing description is merely illustrative of a preferred embodiment of the invention, and that the scope of the invention therefore is not to be limited thereto but is to be determined by the appended claims.

I claim:

1. In an apparatus for quenching a metal rod including means for holding said rod to prevent changes in shape tending to result from said quenching, and means for directing quenching liquid into contact with said rod, said first named means including a supporting member for said rod, and a second member for holding said rod against said supporting member including a series of flange-like walls extending from said second member and positioned along the length of said rod, each of said flange-like walls being formed with a recess therein effective to at least partially embrace said rod, said second named means comprising means for directing a plurality of separate streams of quenching liquid between successive ones of said walls and into contact with the intervening portions of said rod, said partially embracing recesses being effective to hold said rod tightly against said supporting member and being further effective to prevent movement of said rod in either a vertical direction or in a horizontal direction transverse to the axis of said rod.

2. In an apparatus for quenching a metal automobile tie rod of a general U-shape and having fastening eyes adjacent the end portions thereof, means for directing quenching liquid into contact with said rod, and means for holding said rod against changes in shape in either a horizontal or a vertical direction, said holding means including a supporting member for supporting said U-shaped rod on one side thereof, and a second member for holding said rod against said supporting member, said second member comprising a series of flange-like walls extending from said second member and positioned along the length of said rod, each of said flange-like walls being formed with a recess therein effective to at least partially embrace said rod, spacing pins supported in at least one of said holding members and passing through said eyes adjacent the end portions of said U-shaped tie rod, said means for directing quenching fluid into contact with said rod comprising means for directing a plurality of individual streams into contact with said rod and between successive ones of said walls, said partially embracing recesses being effective to hold said rod tightly against said supporting member and to prevent movement of said rod in a vertical direction or in a horizontal direction transverse to the axis of said rod, said pin members being efiective to maintain the spacing between the eyes formed in the end portions of said rod.

3. In an apparatus for quenching an automobile tie rod of a generally U-shape and having connecting eyes formed. adjacent the end portions thereof, said rod being generally circular in cross-section intermediate said eyes, said apparatus comprising a lower die member formed with a substantially plain supporting surface for supporting said tie rod intermediate said connecting eyes in tangential contact therewith, an upper holding die for holding said intermediate portions of said tie rod in contact with said supporting surface formed with a series of recessed chambers in the under side thereof, said chambers being defined in part by downwardly extending separating flange-like partitions, each of said partitions being formed with an arcuate recess complementary in contour and in position to successive portions of said rod and at least partially embracing the same, a pair of pins sup ported in at least one of said die members and passing through said eyes in the end portions of said tie rod, means for introducing an individual stream of quenching medium into each of said recessed chambers and directing the same into contact with the intervening portions of said rod whereby to rapidly and uniformly quench said rod, said arcuate recesses being effective to prevent the movement of portions of said rod in contact therewith in either a horizontal or a vertical direction and said pin members being effective to maintain the spacing between said attaching eyes.

ROY C. INGERSOLL. 

